I was at the NTC's last year as a referee and we where told that you are allowed to switch to your break cue to perform a jump shoot as long as the cue did not have a phenolic tip; it must be a leather tip.
Congrats.
My team qualified as well, but I have decided to go out as a referee this year, so I gave my spot on the team to another shooter from the team we beat in the finals.
Good luck...